The present invention relates generally to insulated shipping containers and relates more particularly to insulated pallet shipping containers.
Insulated shipping containers of the type used to transport temperature sensitive materials, such as biological and/or pharmaceutical products, are well-known. Examples of such containers include U.S. Pat. No. 5,897,017, inventor Lantz, which issued Apr. 27, 1999; U.S. Pat. No. 6,257,764, inventor Lantz, which issued Jul. 10, 2001; U.S. Pat. No. 5,924,302, inventor Derifield, which issued Jul. 20, 1999; and U.S. Pat. No. 6,868,982, inventor Gordon, which issued Mar. 22, 2005, all of which are incorporated herein by reference.
Of the above patents, U.S. Pat. No. 6,868,982 is illustrative, this patent disclosing an insulated shipping container and a method of making the same. In a preferred embodiment, the insulated shipping container comprises an outer box, an insulated insert, an inner box and a closure member. The outer box, which is preferably made of corrugated fiberboard, comprises a rectangular prismatic cavity bounded by a plurality of rectangular side walls, a closed bottom end, and top closure flaps. The insulated insert is snugly, but removably, disposed within the outer box and is shaped to define a rectangular prismatic cavity bounded by a bottom wall and a plurality of rectangular side walls, the insulated insert having an open top end. The insulated insert is made of a foamed polyurethane body to which on all sides, except its bottom, a thin, flexible, unfoamed polymer bag is integrally bonded. The bag is a unitary structure having a generally uniform rectangular shape, the bag being formed by sealing shut one end of a tubular member with a transverse seam and forming longitudinal creases extending from opposite ends of the seam. The inner box, which is snugly, but removably, disposed within the insert, is preferably made of corrugated fiberboard and is shaped to include a rectangular prismatic cavity bounded by a plurality of rectangular side walls and a closed bottom end, the top end thereof being open. The closure member is a thick piece of foam material snugly, but removably, disposed in the open end of the inner box.
Although the shipping containers described above are suitable for many purposes, these containers are not particularly well-suited for transporting large payloads, such as pallet-sized payloads. As a result, other types of insulated shipping containers have been designed to transport larger payloads. Examples of such containers include U.S. Pat. No. 5,669,233, inventors Cook et al., which issued Sep. 23, 1997; U.S. Pat. No. 5,791,150, inventors Bosher et al., which issued Aug. 11, 1998; U.S. Pat. No. 6,266,972, inventor Bostic, which issued Jul. 31, 2001; U.S. Pat. No. 7,028,504, inventor Derifield, which issued Apr. 18, 2006; and U.S. Pat. No. 7,225,632, inventor Derifield, which issued Jun. 5, 2007, all of which are incorporated herein by reference.
Notwithstanding the above, there currently exists a need for an insulated shipping container that is capable of accommodating a larger payload, such as a pallet-sized payload, and that is capable of maintaining the payload within a desired temperature range, e.g., between 2° C. and 8° C. while being subjected to summer-like and/or winter-like ambient temperatures, for an extended period of time, e.g., up to several days or longer.